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What element is defined by the following information? 18 protons, 22 neutrons, 18 electrons

Ionic bond is formed by transfer of [1] from metal to [2]. [3] bond is when atoms [4] one, two or three pairs of electrons.

In [1] and liquids particles are close together. In [2] particles are far apart, so gases are compressible.

Calculate the atomic mass of fictional element “X”, if it has 2 naturally occurring isotopes with the following masses and natural abundances: X-45    44.8776 amu   32.88% X-47    46.9443 amu

A piece of metal ore weighs 8.25 g. When a student places it into a graduated cylinder containing water, the liquid level rises from 21.25 mL to 26.47 mL. What is the density of the ore? (d = m / V, 1 mL = 1 cm3)

Classify each of the following as a physical or chemical change.

Melting and boiling are physical changes.

In the film on lizard evolution, Losos examined the same stretch of DNA from many species to  uncover their evolutionary relationships. The results supported the hypothesis that  lizards on  each island tend to be more closely related to each other, than to similar-looking lizards on  different islands. That means that generally the same types of lizards evolved independently on  each island.

Calculate the molar mass of CuSO4·6H2O, copper sulfate hexahydrate

How many electrons are in nitrogen ion, N3-?